Pete Wolfinger, founder of Peter Built, Co. (now Scuba Tools, Inc.). and author of scuba Regulator Savvy, has written the industry preferred guide on regulator maintenance and repair. It contains almost 200 pages packed with diagrams and valuable information. Available in a spiral bound or loose-leaf ring bound edition, Regulator Savvy explains the science behind how regulators work and serves as an excellent generic course on regulator maintenance and repair. Buy it here.